<%--
  Created by IntelliJ IDEA.
  User: dllo
  Date: 18/5/16
  Time: 下午3:30
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<%
 String username =(String) session.getAttribute("username");
 if(username==null){
 //没有登录
 //请求重定向 到登录页面
 response}
%>
</body>
</html>
